The arrival of large numbers of Slovak Roma to Sheffield over a rather short period has inserted two new languages (Slovak and Romani) into an already diverse, multilingual school environment. Schools face challenges in welcoming the new migrant children, inducting and integrating them and easing access to the English school curriculum. This article draws on longitudinal ethnolinguistic research in one secondary school in Sheffield that has experienced this migration and language situation and responded in a variety of ways. Employing an analytical framework based upon “language-in-education planning” (LEP, [Kaplan & Baldauf, 1997 Kaplan, R. B., & Baldauf, R. B. (1997). Language planning. From practice to theory. Clevedon: Multilingual Matters., Language planning. From practice to theory. Clevedon: Multilingual Matters]) and “micro language planning” (MLP, [Liddicoat & Taylor-Leech, 2014 Liddicoat, A. J., & Taylor-Leech, K. (2014). Micro language planning for multilingual education: Agency in local contexts. Current Issues in Language Planning, 15(3), 237–244. [Taylor & Francis Online], Micro language planning for multilingual education: Agency in local contexts. Current Issues in Language Planning, 15(3), 237–244]), the various emergent practices are explored. Findings display that the school is engaging in various “unplanned” practices to surmount the language and pedagogical issues, thus pointing out the role of MLP as a necessary part of more macro LEP processes.